The present invention relates generally to water filter cartridges used in home and business water filter systems, and optionally used in commercial applications. Current filter systems have a manifold with a manifold inlet port connected to a source of water and a manifold outlet port connected to a dispenser for the filtered water, such as a household refrigerator, or an apparatus using filtered water such as a coffee maker. The manifold typically has a cylindrical, cup shaped interior with one or more receptacles for an inlet and outlet nozzle, and occasionally a recess for a bypass valve actuator. If the inlet and outlet nozzles are coaxial then there is usually one receptacle for the inlet and outlet flow of unfiltered and filtered water, respectively. One example of a water filter cartridge and manifold with separate inlet and outlet nozzles and a protrusion for activating a bypass valve is found in U.S. Pat. Nos. 6,610,932 and 7,147,773.
The filters are held in the manifold by bayonet lugs on the cartridge neck, or by cams or mounting assemblies on the elongated body of the filter cartridge. Examples of such mounting assemblies on the filter cartridge are found in U.S. Pat. Nos. 7,147,773 and 8,627,675.
One difficulty with the above filter cartridges is that occasionally the water in the manifold becomes cold enough to freeze and then the filter cartridge is difficult to extract from the manifold and from the retaining mechanism. U.S. Pat. No. 8,627,675 uses a lever insertion and removal mechanism and the mechanical advantage offered by the lever helps remove filter cartridges where the inlet or outlet has frozen. But even with the removal achieved users typically want to quickly clear the ice from the inlet or outlet and immediately reinsert the filter cartridge for use and the current nozzle and manifold designs make that difficult. There is thus a need for an improved filter cartridge that makes it easier to clear ice from frozen inlet or outlet nozzles in the cartridge, and that facilitates clearing ice from the manifold inlet and outlet receptacles.
Additionally, a number of existing manifolds have the inlet, outlet and bypass valve at specific distances and locations relative to each other, such as specified in U.S. Pat. No. 7,610,932. There is a need for a filter cartridge that makes it easier to clear ice from the cartridge inlet and outlet nozzles while tube within those existing manifold designs requiring inlet and outlet nozzles at predetermined locations relative to each other and relative to a protrusion that actuates a bypass valve in the manifold.